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Rare Metals 2024年第7期43卷 3356-3369页

作者： Aydar Rakhmatullin Franti?ek ?imko Didier Zanghi Zuzana Netriová Ilya B.Polovov Ayrat Dimiev Konstantin V.Maksimtsev Catherine Bessada Michal Korenko conditions extrêmes et materiaux:haute température et irradiation CEMHTIUPR 3079-CNRS Univ Orleans Department of Molten Systems Institute of Inorganic ChemistrySlovak Academy of Sciences Centre of Excellence for Advanced Materials Application-CEMEA Slovak Academy of Sciences Department of Rare Metals and Nanomaterials Institute of Physics and TechnologyUral Federal University Alexander Butlerov Institute of Chemistry Kazan Federal University

For the first time,the mechanism of metal aluminum dissolution in NaF-ScF3eutectic melts and the chemical interaction between the constituents of this mixture have been thoroughly studied by a combination of differential thermal analysis（DTA）,high temperature and solid-state nuclear magnetic resonance（NMR）,and X-ray diffraction（XRD） coupled with the molecular dynamic *** formation of an insoluble Al3Sc alloy in molten（NaF-ScF3）eutsystem was proven,and the chemical mechanism of this aluminothermic Al3Sc alloy production was *** ex situ examinations bring to light the formation of NaScF4and solid solution of Na3（Al,Sc）F6in cooled *** molecular dynamics calculations of the bath allow us to construct the structural model and to predict viscosity,density and electrical conductivity of the reagent melt to help to optimize the conditions of the alloy synthesis.

关键词： Scandium Alloy Molten salts NMR Molecular dynamics

Geochemistry, mineral paragenesis and geothermal conditions of oreforming fluids from the Ain El Bey Cu–Fe deposit: potential occurrence of native gold and precious metal traces (North African orogenic belt, Northern Tunisia)

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Acta Geochimica 2024年第2期43卷 366-384页

作者： Rania Ben Aissa Wiem Ben Aissa Said Tlig Lassaad Ben Aissa Abdessalem Ben Haj Amara Faculty of Science of Bizerte University of Carthage7021 ZarzounaBizerteTunisia Laboratoire de Recherche Ressources Materiaux et EcosystemesUniversity of Carthage7021 ZarzounaBizerteTunisia Department of Geology University Claude Bernard Lyon 169622 VilleurbanneFrance Faculty of Science of Tunis University of Tunis-El ManarRommana1068 TunisTunisia

The Ain El Bey abandoned mine, in North-West Tunisia, fits into the geodynamic context of the European and African plate boundary. Ore deposit corresponds to veins and breccia of multiphase Cu–Fe-rich mineralization related to various hydrothermal fluid circulations. Petromineralogical studies indicate a rich mineral paragenesis with a minimum of seven mineralization phases and, at least, six pyrite generations. As is also the case for galena and native silver, native gold is observed for the first time as inclusion in quartz which opens up, thus, new perspectives for prospecting and evaluating the potential for noble metals associated with the mineralization. Scanning Electron Microscope--Energy Dispersive Spectroscopy and Transmission electron microscopy analyses show, in addition, a large incorporation of trace elements, including Ag and Au, in mineral structures such as fahlores(tetrahedrite-tennantite) and chalcopyrite ones. The mineral/mineral associations, used as geothermometers, gave estimated temperatures for the mineralizing fluids varying from 254 to 330 ℃ for phase Ⅲ, from 254 to 350 ℃ for phase Ⅳ, and from 200 to 300 ℃ for phases Ⅴ and Ⅵ. The seventh and last identified mineralization phase, marked by a deposit of native gold, reflects a drop in the mineralizing fluid’s temperature(conditions. Such results open up perspectives for the development of precious metal research and the revaluation of the Cu–Fe ore deposit at the Ain El Bey abandoned mine, as well as at the surrounding areas fitting in the geodynamic framework of the Africa-Europe plate boundary.

关键词： Ore-formingﬂuids Mineral geochemistry Mineral geothermometers Native silver-gold Ain El Bey Ore deposit North Tunisia

Samarium( II )-electrocatalyzed chemoselective reductive alkoxylation of phthalimides

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Organic Chemistry Frontiers 2022年第5期9卷 1308-1314页

作者： Yu-Feng Zhang Mohamed Mellah Universite Paris-Saclay CNRSInstitut de Chimie Moleculaire et des Materiaux d’OrsayBatiment 42091405 OrsayFrance

The unprecedented samarium electrocatalyzed reductive alkoxylation of phthalimides in a single step is *** mild conditions,using electrogenerated Sm(II)with TMSCl(trimethyl chlorosilane),N-substituted 3-alkoxyl isoind... 详细信息

关键词： catalyzed reductive substituted

Role of the rhizosphere of a flooding-tolerant herb in promoting mercury methylation in water-level fluctuation zones

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Journal of Environmental Sciences 2022年第9期34卷 139-151页

作者： Juan Wang Yuping Xiang Xiaosong Tian Cheng Zhang Guiqing Gong Jinping Xue Tao Jiang Dingyong Wang Yongmin Wang Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin College of Resources and EnvironmentSouthwest UniversityChongqing 400715China Laboratory of Environmental Nanotechnology&Health Effect Chinese Academy of SciencesResearch Center for Eco-Environmental SciencesBeijing 100085China College of Resources and Safety Chongqing Vocational Institute of EngineeringChongqing 402260China Institut des Sciences Analytiques et des Physico-Chimie pour l’Environnement et les materiaux(IPREM) UMR 5254CNRSUniversitede Pau et des Pays de l’AdourPau 64000France

The water-level fluctuation zone(WLFZ) has been considered as a hotspot for mercury(Hg) methylation. Flooding-tolerant herbs are gradually acclimated to this water-land ecotone, tending to form substantial root systems for improving erosion resistance. Accompanying rhizosphere microzone plays crucial but unclear roles in methylmercury(Me Hg) formation in the WLFZ. Thus, we conducted this study in the WLFZ of the Three Gorges Reservoir, to explore effects of the rhizosphere of a dominant flooding-tolerant herb(bermudagrass) on Me Hg production. The elevated Hg and Me Hg in rhizosphere soils suggest that the rhizosphere environment provides favorable conditions for Hg accumulation and methylation. The increased bioavailable Hg and microbial activity in the rhizosphere probably serve as important factors driving Me Hg formation in the presence of bermudagrass. Simultaneously, the rhizosphere environments changed the richness, diversity, and distribution of hgc A-containing microorganisms. Here, a typical ironreducing bacterium( Geobacteraceae) has been screened, however, the majority of hgc A genes detected in rhizosphere, near-, and non-rhizosphere soils of the WLFZ were unclassified. Collectively, these results provide new insights into the elevated Me Hg production as related to microbial processes in the rhizosphere of perennial herbs in the WLFZ, with general implications for Hg cycling in other ecosystems with water-level fluctuations.

关键词： Three Gorges Reservoir Water-level fluctuation zone Rhizosphere soil Methylmercury Mercury methylator

Static and dynamic stability responses of multilayer functionally graded carbon nanotubes reinforced composite nanoplates via quasi 3D nonlocal strain gradient theory

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Defence Technology（防务技术） 2022年第10期18卷 1778-1809页

作者： Ahmed Amine Daikh Mohamed Sid Ahmed Houari Mohamed Ouejdi Belarbi Salwa A.Mohamed Mohamed A.Eltaher Laboratoire D'etude des Structures et de Mecanique des materiaux Departement de Genie CivilFacultedes Sciences et de La TechnologieUniversite Mustapha Stambouli B.P.305R.P.29000MascaraAlgeria Laboratoire de Genie Energetique et materiaux LGEMUniversite de BiskraB.P.145R.P07000BiskraAlgeria Department of Engineering Mathematics Zagazig UniversityP.O.Box 44519ZagazigEgypt Faculty of Engineering Mechanical Engineering DepartmentKing Abdulaziz UniversityP.O.Box 80204JeddahSaudi Arabia Faculty of Engineering Mechanical Design and Production DepartmentZagazig UniversityP.O.Box 44519ZagazigEgypt

This manuscript presents the comprehensive study of thickness stretching effects on the free vibration,static stability and bending of multilayer functionally graded(FG)carbon nanotubes reinforced composite(CNTRC)*** nanoscale and microstructure influences are considered through a modified nonlocal strain gradient continuum *** on power-law functions,four different patterns of CNTs distribution are considered in this analysis,a uniform distribution UD,FG-V CNTRC,FG-X CNTRC,and FG-O CNTRC.A 3D kinematic shear deformation theory is proposed to include the stretching influence,which is neglected in classical ***'s principle is applied to derive the governing equations of motion and associated boundary *** solutions are developed based on Galerkin method to solve the governing equilibrium equations based on the generalized higher-order shear deformation theory and the nonlocal strain gradient theory and get the static bending,buckling loads,and natural frequencies of *** with previous works is presented.A detailed parametric analysis is carried out to highlight the impact of thickness stretching,length scale parameter(nonlocal),material scale parameter(gradient),CNTs distribution pattern,geometry of the plate,various boundary conditions and the total number of layers on the stresses,deformation,critical buckling loads and vibration *** new results are also reported in the current study,which will serve as a benchmark for future research.

关键词： 3D shear deformation theory Free vibration Buckling Bending Galerkin method Functionally graded nanotube Nonlocal strain gradient theory

Thermoluminescent response of gamma irradiated Na^(+)–Cu^(+) ionexchanged silicate glass in large dose range

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Nuclear Science and Techniques 2023年第5期34卷 22-32页

作者： Safa Toumi Khaled Farah Laboratoire de Physico‑Chimie des Matériaux Département de PhysiqueFacultédes Sciences de MonastirUniversitéde MonastirMonastirTunisia Institut Supérieur du Transport et de la Logistique de Sousse Universitéde Sousse4023 SousseTunisia Laboratoire de Recherche en Energie et Matière Développement des Sciences Nucléaires(LR16CNSTN02)Centre National des Sciences et Technologies Nucléaires2020 Sidi‑ThabetTunisia

The introduction of metals into vitreous matrices is the origin of various interesting phenomena;in particular,the presence of copper ions in glass has been the subject of considerable research because of its numerous *** ion-exchange process is primarily used to introduce copper ions into glass *** thermoluminescence(TL)of silicate glass was studied to evaluate its potential as gamma-sensitive material for dosimetric applications;the effect of copper doping on the thermoluminescent sensitivity was investigated using the Cu-Na ion-exchange technique for different concentrations and doping conditions,over a wide dose range of 10 mGy to 100 *** results showed that Cu doping significantly improved the sensitivity of the glasses to gamma *** the ion-exchange,two peaks appeared in the glow curves at approximately 175 and 230°C,respectively,which possibly originated from the Cu^(+) centers,along with a weak TL peak at around 320℃.We also attempted to explain the origin of the observed thermoluminescence by exploiting the Electron paramagnetic resonance(EPR)*** results clearly show quenching of the TL emission with increasing copper *** present work indicates that the thermoluminescence response of these glasses to gamma rays can be reasonably measured in the range of 0.001-100 *** study also facilitates the understanding of the basic TL mechanism in this glass system.

关键词： Cu-Na ion-exchange Silicate glass Thermoluminescence Gamma irradiation Electron paramagnetic resonance

Numerical Study of Greenhouse Nocturnal Heat Losses

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Journal of Thermal Science 2011年第4期20卷 377-384页

作者： F.Berroug E.K.Lakhal M.El Omari M.Faraji H.El Qarnia Laboratoire d'Automatique de l'Environnement et Procédés de Transfert UniversitéCadi AyyadFacultédes Sciences Semlalia-Département de PhysiqueMarrakech-MarocAffiliéau CNRSTURAC 28 Laboratoire de Physique des materiaux MicroelectroniqueAutomatique et TechniqueDepartement de PhysiquesFaculte des Sciences Ain ChockUniversite Hassan IICasablanca-Maroc

In this study we quantify and analyze different components of nocturnal losses from a heated greenhouse with the presence of vegetation for typical winter weather conditions in Marrakesh-Morocco,using a non linear model,based on the greenhouse heat and mass *** was found that 12% of the total input heat was dissipate as a sensible and latent leakage losses,66% was lost by convective exchange through air-inner *** gain of energy at the inner-cover is dissipated at the outer-cover by radiation(66%)and convection(34%).This results point toward some practical measures to reduce heat losses:increasing air tightness,using covering materials with low-emissivity in the long wave band or putting up an external thermal curtain should provide significant energy savings.

关键词：热损失数值研究温室热量损失非线性模型天气条件组成部分质量平衡

Ageing evaluation of cable insulations subjected to radiation ageing:Application of principal component analyses to Fourier Transform Infra-Red and dielectric spectroscopy

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High Voltage 2022年第4期7卷 652-665页

作者： Simone Vincenzo Suraci Sandrine Amat Lea Hippolyte Astrid Malechaux Davide Fabiani Claire Le Gall Océane Juan Nathalie Dupuy LImes Department of ElectricalElectronic and Information EngineeringUniversity of BolognaBolognaItaly Aix Marseille University Avignon UniversitéCNRSMarseilleFrance Institut de Radioprotection et de Sûreté Nucléaire MarseilleFrance

The evolution of properties of crosslinked polyethylene(XLPE)-based insulating mate-rials under radio-chemical ageing conditions is presented and *** total,seven different polymer compounds were tested,characterised by an increasing quantity of additives,for example,antioxidants(AOs)and fillers as flame *** were analysed using different testing techniques,that is,Fourier Transform Infra-Red and dielectric *** allowed a broad characterisation of the polymer,bringing to good correlations between the arising of new chemical groups caused by ageing and the modifications on the complex ***-based AOs are found to be the most efficient in terms of protection against *** the contrary,flame retardants are concluded not to have any impact on the material *** data were then treated using the principal component *** data treatment successfully distinguished the material composition(with and without additives)and the ageing *** results confirm the relevance of this analysis in understanding the impact of irradiation on the chemical and functional properties of the polymer materials studied.

关键词： component principal bringing

Role of the porphyrins and demulsifiers in the aggregation process of asphaltenes at water/oil interfaces under desalting conditions:a molecular dynamics study

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Petroleum Science 2020年第3期17卷 797-810页

作者： H.Santos Silva A.Alfarra G.Vallverdu D.Bégué B.Bouyssiere I.Baraille Institut des Science Analytiques et Physico-Chimie pour l’Environnement et les materiaux UMR 5254CNRS/Univ Pau&Pays Adour64000 PauFrance Total Research and Technology GonfrevilleBP 2776700 HarfleurFrance Joint Laboratory C2MC:Complex Matrices Molecular Characterization Total Research and TechnologyGonfrevilleBP 2776700 HarfleurFrance

Breaking water-in-oil emulsions during the refining of crude oils is an important step before any upgrading process is *** molecules are incriminated as playing an important role in this *** the mechanisms behind the affinity between them and water is a key step to understand how to break these emulsions more easily and require lower amounts of *** which demulsifier molecule(s)to use is also primordial,but to do so rationally,one needs to know which are the molecular interactions in place between asphaltenes,porphyrins and water so that demulsifiers are chosen to destabilize a specific physical–chemical *** this paper,we study the interactions arising between asphaltenes and porphyrins and six different molecules potentially displaying a demulsification action in the presence of water/oil *** demonstrate that the ionic demulsifier molecules present an interesting potential to either interact strongly with water,replacing asphaltenes in this interaction,or to interact with the active sites of asphaltenes,deactivating them and avoiding any asphaltenic interfacial ***,we also found that although asphaltenes do not migrate spontaneously toward the water/oil interfaces,porphyrins do so rather *** indicates that porphyrins do have an important activity at the water/oil interface.

关键词： Asphaltenes aggregation Petroporphyrins Molecular dynamics Emulsion Water-oil interface Demulsifiers

Synthesis of (B-C-N) Nanomaterials by Arc Discharge Using Heterogeneous Anodes

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Plasma Science and Technology 2016年第5期18卷 465-468页

作者： Djamel Eddine GOURARI Manitra RAZAFINIMANANA Marc MONTHIOUX Raul ARENAL Flavien VALENSI Sebastien JOULIE Virginie SERIN LAPLACE (Laboratoire Plasma et Conversion d'Energie) CNRS-INPT-Universite Toulouse III 118 Route de Narbonne 31062 Toulouse Cedex 9 France CEmes (Centre d'Elaboration des materiaux et d'etudes Structurales) CNRS-Universite Toulouse III 29 rue Jeanne Marvig F-31055 Toulouse Cedex 4 France Instituto de Nanociencia de Aragon (INA) Universidad de Zaragoza Calle Mariano Esquillor 50018 Zaragoza Spain

In spite of the current prevalence of the CVD-based processes, the electric arc remains an interesting process for the synthesis of carbon nanoforms, thanks to its versatility, robustness and easiness. It also allows performing in-situ substitution of carbon atoms by hetero-elements in the graphene lattice. Our work aims to establish a correlation between the plasma properties, type and chemical composition （and the substitution rate） of the obtained single-wall carbon nan- otubes. The plasma was characterized by optical emission spectroscopy and the products were analyzed by high resolution transmission electron microscopy and core level Electron Energy-Loss Spectroscopy （EELS）. Results show that a high boron content leads to a plasma temperature decrease and hinders the formation of nanotubes. This effect can be compensated by increasing the arc current and/or yttrium content. The optimal conditions for the synthesis of boron- and/or nitrogen-substituted nanotubes correspond to a high axial plasma temperature associated to a strong radial gradient. EELS analysis confirmed that the boron incorporates into the graphenic lattice.

关键词： arc discharge plasma nanomaterials synthesis optical spectroscopy boronnitride doped carbon nanotubes HRTEM EELS